Northern UTA220/UTA220k - Manual (Page 86)

12-10
UTA220/UTA220k
D-Channel X.25
PAD Select
This command establishes an X.25 virtual call connection
through the ISDN packet handler to a remote host or device.
The contents of the PAD select command determine the
contents of the X.25 Call Request packet. The format can be
in any of following three forms:
-
user data>
-
The facility request block permits the user to request special
services from the ISDN network. If more than one facility is
specified, a comma must separate each facility. The end of the
facility request block must be followed by the hyphen
character.
The address block specifies the called Network User Address
(NUA). The address cannot exceed 15 characters in length.
Abbreviated or multiple addresses are not supported.
The call user data field cannot exceed 12 characters in length
(including spaces) and must be preceded by either the P or D
character. Carriage returns and the + character are not
considered part of the user data field because they are treated
as PAD command delimiters.
Response:
COM - Indicates the virtual call is established.
ERR - Indicates the PAD is in an unknown mode that cannot
allow the PAD select command, the PAD has been initialized
in the off-line mode (i.e., no virtual call connection has been
established), or the PAD select command is invalid due to a
format error. Some PAD select format errors are as follows:
• The facilities block is not followed by the - character.
• The CUG facility is requested and two decimal digits are not
specified.
• The RPOA facility is requested and four decimal digits are
not specified.
• The address block length exceeded 15 characters.
• The call user data block is not preceded by the P or D
character.
• The call user data block length exceeded 12 characters.
• An invalid facility is requested as the first facility in the
facility request block.
CLR xxx - Indicates the attempted call has cleared. The xxx
is the ASCII character cause code which specifies the reason
the call attempt cleared (see PAD Clear Service Signals).